Information on a measure related to obesity has been obtained on over 3000 Amish individuals. Segregation analysis has been done on the trait with the best fitting model being an autosomal dominant model adjusted for age and sex effects. The model has been used to identify 20 families that will be most informative for linkage analysis. Additional phenotyping will be funded through the German Government. Genotyping will be done in the Medical Genetics Branch of NHGRI. Markers will be determined in an attempt to identify genetic components for traits related to obesity in the Amish.